Have you heard of HIIT? You might have seen it advertised at your local gym or as the topic of your favorite morning talk show. High intensity interval training (HIIT) is taking the fitness world by storm as the hottest way to get an effective, quick workout in from anywhere!

In order to understand how HIIT affects the inner workings of your muscles and organs, we have to hit the textbooks. HIIT’s popularity has encouraged scientists around the world to take a closer look into how this rigorous routine transforms the body in the short-term and long-term. The results are in: HIIT does a lot of great work on the body.

From shedding fat to boosting heart health, HIIT can help you lead an overall healthier life. Explore some of the science behind HIIT below and get pumped to add this hot exercise trend into your routine.


People love HIIT because you can get lasting benefits from a quick 20-minute workout. The idea of reducing your workout from an hour to 20 minutes can seem counterproductive, but not when you are switching to HIIT. Even if you are physically exercising for only 20 minutes, your body continues to work harder for hours, even if you are resting or going back to work during that time.

Why? The answer lies in your ability to consume and use oxygen.

When you perform aerobic exercises, like the ones you do in HIIT routines, your body requires a healthy flow of oxygen to keep your muscles working. When your workout is as intense as a HIIT workout, you deplete your body of oxygen. This sends your body into a process called Excess Post-Exercise Oxygen Consumption (EPOC.) In order to restore your body to healthy oxygen levels, your body continues to work and burn calories after your HIIT session is over. You continue to reap the benefits of HIIT for up to 24 hours; that’s why experts recommend only doing HIIT routines up to three times a week.

EPOC also boost your body’s metabolic rate. As your body works to “catch up” with EPOC, it ramps up a process called “triglyceride cycling.” Triglyceride cycling is the transition your body makes from using carbohydrates to fat as a main energy source. Once you have exhausted all the excess carbs in your body, you turn to stored fat and start to burn through that. HIIT is great for shedding fat, even the kind that is hardest to lose.

It is worth noting here that your diet plays a part in your ability to get the results you want from HIIT. If you are overloading on carbohydrates, your body will not need to dip into excess fat storage to produce energy. Consult with a nutritionist about your exercise routine and the right amount of carbs, fat, and protein necessary to reach your weight and fitness goals.

HIIT Is an Investment in Your Health

Science behind HIIT doesn’t just look at how high-intensity interval training affects your body in the short term. Many studies look at the long-term benefits that regular HIIT routines can have on your overall health.


Studies have shown that even a shorter HIIT workout increases muscular endurance. When our muscles can endure exercise for longer periods of time, we give ourselves more opportunities to build muscle and shed fat. Over time, HIIT workouts can be increased and help us reap even more benefits.

HIIT and Heart Health

HIIT also helps to increase cardiovascular health. The fat-burning benefits of HIIT contribute to overall heart health, and the intensity of the exercise makes your heart stronger. Fitness experts have said that if you are not hitting 80% of your optimal heart rate during your HIIT routine, you need to push yourself further. When you are consistently reaching these levels, your heart becomes more accustomed to working hard and keeping your body moving. Even just a weekly, 22-minute HIIT session can increase cardiovascular health and decrease the risk of disease or failure.

How HIIT Affects Blood Sugar

The content of your blood that pumps throughout your body is affected by HIIT and exercise. When you exercise, your liver starts to produce glucose that is sent into your bloodstream. This glucose helps your muscles to give your muscles energy to function throughout your workout. But once the glucose is produced, it doesn’t automatically work its magic on your muscles; it needs to recruit the services of insulin.

Regular HIIT workouts has been proven to improve insulin sensitivity. Insulin can perform its job better and maintain healthy blood sugar levels while keeping the muscles energized. Blood sugar that is too low or too high can result in a range of unhealthy consequences, including diabetes. The science behind HIIT shows a direct correlation between HIIT workouts and a decreased risk of type 2 diabetes. If you have diabetes in your family, or have been told that you pose a high risk of getting diabetes, you should really consider adding HIIT to your exercise routine.

HIIT is not just a workout; it’s an investment in your overall health. By adding HIIT into your exercise routine, you set your body up to work harder throughout the day to burn fat, build muscle, and live an overall healthier life.

Before you start to explore HIIT routines at home or at the gym, consult with your doctor. Initial health concerns, including diabetes or obesity, may affect the duration, frequency, and intensity of your first weeks of HIIT.

How To Start Meeting Your Fitness Goals with HIIT

Whether you want to shed fat, build muscle, or become a better athlete, you can reach your goals with HIIT. As the science behind HIIT continues to prove the benefits of this routine, it will continue to be a hot trend in gyms and fitness centers throughout the country.

HIIT can be performed with many different intervals and routines. At beatStrong, we make HIIT routines easy. Our group fitness classes give participants an effective HIIT routine that keeps your body working even after you leave the gym. Head over to our fitness center and try out a class for yourself. Once you start to feel the science behind HIIT having an effect on your body, you’ll keep coming back for more!

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